package com.smart.framework.util;


import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.FileFilter;
import java.io.IOException;
import java.net.URL;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Set;

/**
 * <p><b>Description:</b>  TODO
 * <p><b>Company:</b>
 *
 * @author created by Jesse Xu at 10:27 on 2019/9/23
 * @version V0.1
 * @classNmae ClassUtil
 */
public final class ClassUtil {

    private static final Logger LOGGER = LoggerFactory.getLogger(ClassUtil.class);

    public static ClassLoader getClassLoader() {
        return Thread.currentThread().getContextClassLoader();
    }

    public static Class<?> loadClass(String className, boolean isInitialized) {
        Class<?> cls = null;
        try {
            cls = Class.forName(className, isInitialized, getClassLoader());
        } catch (ClassNotFoundException e) {
            LOGGER.error("load class failure", e);
            throw new RuntimeException(e);
        }
        return cls;
    }

    public static Set<Class<?>> getClassSet(String packageName) {
        Set<Class<?>> classSet = new HashSet<Class<?>>();
        try {
            Enumeration<URL> urls = getClassLoader().getResources(packageName.replace(".", "/"));
            while (urls.hasMoreElements()) {
                URL url = urls.nextElement();
                if (url != null) {
                    String protocol = url.getProtocol();
                    if (protocol.equals("file")) {
                        String packagePath = url.getPath().replace("%20", " ");
                        addClass(classSet, packagePath, packageName);
                    }
                }

            }
        } catch (IOException e) {
            LOGGER.error("get class set failure", e);
            throw new RuntimeException(e);
        }
        return null;
    }

    private static void addClass(Set<Class<?>> classSet, String packagePath, String packageName) {
        File[] files = new File(packagePath).listFiles(new FileFilter() {
            public boolean accept(File file) {
                return (file.isFile() && file.getName().endsWith(".class")) || file.isDirectory();
            }
        });

        for (File file : files) {
            String fileName = file.getName();
            if (file.isFile()) {
                String className = fileName.substring(0, fileName.lastIndexOf("."));
                if(StringUtils.isNotEmpty(packageName)){
                    className = packageName.concat(".").concat(className);
                }
                doAddClass(classSet,className);
            }else{
                String subPackagePath = fileName;
                if(StringUtils.isNotEmpty(packageName)){
                    subPackagePath = packagePath.concat("/").concat(subPackagePath);
                }
                String subPackageName  = fileName;
                if(StringUtils.isNotEmpty(packageName)){
                    subPackageName = packageName.concat(".").concat(subPackageName);
                }
                addClass(classSet,subPackagePath,subPackageName);
            }
        }
    }

    private static void doAddClass(Set<Class<?>> classSet, String className) {
        Class<?> cls = loadClass(className,false);
        classSet.add(cls);
    }


}
